Portable cabin



FIG. 1 is a front perspective view of a portable cabin showing my new design.

FIG. 2 is a rear perspective view thereof;

FIG. 3 is a side view thereof;

FIG. 4 is an opposite side view thereof;

FIG. 5 is an end view thereof; and,

FIG. 6 is a top plan view thereof. 

CLAIM The ornamental design for a portable cabin, as shown and described. 